The Justice Dept has been investigating this now for weeks.
The statement by the CIA Director while testifying in front of Congress was a shot across the bow, and everyone in DC knows it.
A Grand Jury can be empaneled fairly quickly. Federal Grand Juries are usually about 16 to 23 people. They meet regularly, but I think the frequency varies from one district to another. Grand juries have the power to use subpoenas to gather the evidence they need to use in deciding whether crimes have been committed - and that is what makes everyone who was associated with this leak nervous.
We have to remember that when it is in the hands of a Grand Jury, the spin of "it's all politics" melts away. This is serious business, and people are not playing political games at that point.
The question now it, will the Justice Dept take the next step? If they do, watch the Beltway crowd and the MSM howl.
It is always the hurt hog that squeals.